Wireless communication networks are deployed across large geographic areas in an overlapping manner. At a given geographic location, several different wireless service providers may provide wireless communication service to various customers. The service providers separate themselves from one another by using different radio frequencies for their wireless communications. Thus, multiple wireless service providers use different radio frequencies to maintain separation among their users and networks.
In addition to wireless communication networks, other systems also propagate wireless signals at various frequencies. For example, police and fire personnel utilize certain radio frequencies for their own communications. In another example, weather radar systems propagate wireless signals for Doppler scanning purposes. Thus, a given geographic location may have overlapping radio coverage for wireless service providers, first responders, weather radars, and the like.
The complex collection of radio frequencies at a given location needs to be managed to avoid radio interference. Energy for a radio signal at a first frequency may be shifted to a second frequency by the environment or a system flaw. When conditions cause energy to shift from one frequency to another in our multi-frequency environment, then radio interference results, and the quality of everyone's wireless experience is harmed.
To avoid radio interference between frequencies, wireless systems use electronic filters to control the energy propagation on a per-frequency basis. Unfortunately, the electronic filters may be too expensive or not sufficiently durable for some field applications. Current filter technologies are not efficient and effective enough for today's multi-frequency environment.